The mechanism of replication of Marek's disease herpesvirus genome in cells productively infected with the virus and in lymphoid tumor cells which harbor resident viral genomes is under investigation. The structural and catalytic properties of the Marek's disease herpesvirus-induced DNA polymersase is being studied. The role that the polymerase plays in the replication of the viral genome in cells productively infected with the virus and in tumor cells in being assessed. The mechanism of inhibition by phosphonoacetate of herpesvirus replication is under study. BIBLIOGRAPHIC REFERENCES: Lee, L.F., J.A. Boezi, S.S. Leinbach and J.M. Reno (1975). The DNA Polymerase Induced by Marek's Disease Herpervirus and by the Herpesvirus of Turkeys. Abstracts of the 3rd International Congress of Virology. Madrid, Spain - P-105. (The talk was presented by Dr. Lee). Leinbach, S.S., J.M. Reno, L.F. Lee, A.F. Isbell and J.A. Boezi (1975) Mechanism of Phosphonoacetate Inhibition of Herpesvirus-Induced DNA Polymerase. Biochemistry (to appear in the January 27th, 1976 issue).